Pro…table Innovation Without Patent

Protection: The Case of Derivatives.

Helios Herrera

ITAM

Enrique Schroth1

HEC Lausanne and FAME2

February 10, 2003

1Corresponding author. BFSH 1, 1015 Lausanne, Switzerland. Email: En-rique.Schroth@hec.unil.ch. Tel: +41 21 692 3352. Fax: +41 21 692 3435.

2We are grateful to Douglas Gale, William Baumol, Jean-Pierre Benoît, BoyanJovanovic, Josh Lerner, Giuseppe Moscarini, David Silber and Peter Tufano fortheir advice. All errors in the paper are only ours.

Abstract

Investment banks …nd it pro…table to invest in the development of innovative

derivative securities even without being able to preclude early competition

from other investment banks using patents. To explain this, we assume that

the developer can learn from the …rst issues of the innovative …nancial product

and is able to become the expert issuer by the time imitation enters the

market. We show how this becomes an informational …rst-mover advantage

that turns innovators into the market leader. It is this advantage, and not

the typical temporary monopoly position awarded to a patent holder, that

provides the incentive to pay the development costs. In the aftermath, the

innovator ends up with the largest share of the underwriting market and

makes positive pro…ts. Our model’s predictions are consistent with many

stylized facts of …nancial innovations by investment banks.

JEL Classi…cation: G24, L12, L89.

Keywords: Financial innovation, …rst-mover advantages,

asymmetric information, learning-by-doing.

1 Introduction

1.1 The Motivation

Unlike many innovative products, innovations in …nancial products remain

largely unpatentable.1 Some developments in Industrial Organization Theory

show that, for some industries, patents are the only mechanism that can

make it optimal for …rms to pay the research and development costs (R&D

henceforth) if their invented product would otherwise be reverse-engineered,

produced and marketed by competitors that free-ride R&D. In such type of

models, the free entry eliminates pro…ts and potential innovators will choose

not to invest in R&D without legal protection against imitation.2

Nevertheless, some models of product innovation can generate equilibria

with positive innovator pro…ts even when they cannot patent their discover-

ies.3 One possibility is to assume that the developer has a lead-time over his

1Only recently, in January of 1999, a patent for a “…nancial method or formula” wasupheld by the United States Supreme Court. The State Street Bank of Boston suedto invalidate a patent for a valuation algorithm by the Signature Financial Group ofMassachussetts, arguing that it violated the business method exemption in patent laws.The Supreme Court upheld the patent, setting an important precedent that may makemost innovations in …nance patentable. As Lerner [11] argues, the number of patent …llingsand awards may sharply increase now that the State Street Case has been settled.

2See Tirole [24, Ch. 10] for a description of the reasons why imitation of discoveriesproduces incentives for maintaining low levels of R&D.

3Benoît [3] and Reinganum [19] provide some notable examples.

1

imitators. If this lead-time is long enough or, if R&D costs are small enough,

innovators can earn su¢ciently large monopolist rents prior to imitation so as

to justify the initial R&D expenditures. In essence, this e¤ect is qualitatively

no di¤erent than the e¤ect of a patent. Another possibility is to assume that

clients have costs of switching from the …rst provider of the new service (the

innovator) to the late comers (the imitators). In this case the pioneer can

e¤ectively build large market shares and earn rents.

The delayed imitation hypothesis cannot be reconciled with the most im-

portant pieces of evidence of product innovation in …nance. Tufano [26] found

that periods of “monopolistic” issuing of new …nancial services are relatively

short.4 This makes a strong case against the argument that only su¢ciently

long periods of temporary monopoly make innovations worthwhile. In the

same study, Tufano [26] also found that, for the 58 innovations he studied

between 1974 and 1986, the investment banks that created them could not

charge monopolistic underwriting fees before imitation occurred. Further, al-

though data on innovation costs is not available, anecdotal evidence suggests

4For all the 58 innovations he studied, the median number of underwriting deals com-pleted by the innovating bank prior to entry by rival banks was of only one.

2

that these are not negligible.5,6

As Bhattacharyya and Nanda [4] point out, banks and clients may de-

velop valuable relationships, making it costly for a …rm to switch bankers.

Thus, switching costs can explain why early imitation may not erode an in-

novator’s pro…ts and therefore its incentives to innovate. Evidence gathered

in interviews to bankers by Naslund [15] suggests that switching costs might

not be signi…cant, “the banks mentioned that if one came up with an idea

the innovator became known as the expert and customers would turn to it

even if they used another bank for other services”.7

The clue to what are the advantages to inovators in …nance, despite all

the disadvantages mentioned above, seems to be the fact that investment

banks are able to capture the largest share of underwriting deals using the

product they created. This is found in Tufano’s sample of 58 securities,

where despite being imitated early, the innovators preserve the leadership

5The relevant innovation cost is not only R&D, but all the sunk payments requiredto discover and introduce an innovation. Mans…eld [13] disaggregates them in R&D, thebuilding of production facilities, and marketing. In the IO literature, these costs areusually referred to as R&D. In this paper we follow the IO convention and use the termR&D to refer to total innovation costs.

6 Investment bankers interviewed by Tufano [26] reportedly spent between $50,000 and$5 million to develop each new security. In a study by Naslund[15], marketing costs forinnovations by 20 …nancial institutions range between $1 million and $3 million.

7Krigman, Shaw and Womack [10] mention other reasons why …rms switch underwrit-ers, the most important being the tendency to gradually select more reputed bankers tobene…t from the higher quality of their research analysts.

3

in the long run. Other evidence of innovators becoming market leaders is

found in Reilly [18]: Drexel Burnham Lambert, the pioneer in underwriting

junk bonds had at least a 40% of the market between 1985 and 1988. Also,

according to Mason et. al. [12] First Boston, the innovator of asset-backed

securities, underwrote a share that almost doubled that of the second largest

underwriter in this market between 1985 and 1991. More recently, Schroth

[22] found that for most of the innovative equity-linked securities between

1985 and 2001 the innovators also had the lead in the corporate underwriting

market. For other classes of derivatives the evidence is scarce. In fact, as

Gastineau and Margolis [9] argue, some derivatives markets are not easy to

de…ne and market shares di¢cult to compute or disaggregate. Nevertheless,

they argue that market makers are likely to have the largest market shares,

as observed in the underwriting markets for the securities already mentioned.

Thus, it seems innovation in securities di¤ers qualitatively from other

kinds of product innovation. Most of the research in …nancial innovation has

examined extensively case studies and asked why there was a demand for

some new securities at the time they were introduced.8 In other words, the

8Miller [14], for example, argues that what spurred the latest innovation “wave” wereloopholes in tax codes that provided incentives to design securities that circumventedregulation. Finnerty [8] describes di¤erent ways in which new securities add value andrelates them to corporate …nancial innovations since the 70s. A broader survey of the

4

focus has been, basically, on explaining what made each particular innova-

tion attractive to investors. Not much research, though, has addressed the

question of why an unpatentable innovation is worth its R&D expenditure

if imitation is early and seemingly costless.9 The question we try to answer

here is why do investment banks …nd it privately pro…table to be developers

of marketable …nancial instruments.

1.2 The Agenda

The large variety of innovations observed in …nance induces us to pursue a

theory of innovation speci…c to some kind of …nancial products. Our model

will focus on privately negotiated …nancial contracts that are designed to

transfer the credit exposure of an underlying asset between two parties. As

we will argue later, this type of contracts include several types of private

deals made between competitive investment banks and the holders of claims

to some asset with random payo¤s. These holders may want to issue a new

history …nancial innovation can be found in Tufano [27].9 In a general setting, Boldrin and Levine [6] show how the natural monopoly position

of the innovator as a provider of the original prototype can make the innovative processworthwhile despite imitation. In the case of …nancial innovation, Black and Silber [5]present a model in which the innovator is a futures exchange that develops and advantagefor creating a new contract by providing liquidity for investors earlier than the competingexchanges in order to attract future trades.

5

security whose payo¤ is backed by the cash‡ow of the underlying asset or

may just wan to swap away part of the risky component of the cash‡ow. A

particular characteristic of the market where these deals are made is that the

transactions made, for example, a credit swap or the purchase of a portfolio

of credit card collectibles, are not observable for free. Con…dentiality agree-

ments in these markets are e¤ective mechanisms that allow the banker (e.g.,

an innovator of a derivative) to conceal crucial information from potential

competitors.

It is clear from our motivation that the innovator must have an advan-

tage over its imitators. Since for …nancial innovations the lead-time is on

average short and the development cost is substantial, the innovator must

make supra-normal pro…ts during the imitation stage. After revising some

case studies in innovation in credit derivatives or asset securitization we can

identify a common feature: bankers choose not to disclose the history of deals

they have made but rather disclose only the aggregate dollar amount of the

transactions made in a given period. Presumably, the knowledge of the his-

tory of their deals made is valuable and they are keen not to make it public.

Therefore, the model we present here explains why the innovator extracts

private information from early deals and uses it to compete with its imita-

6

tors once they enter the market. As William Toy, Managing Director at CDC

Capital Inc. puts it, “There is at least a perception that the …rst mover is

more familiar with the product he issues than the imitator”.[25]

In the model, the advantage enjoyed by the …rst-mover will be based on

an information asymmetry: innovators will have had one previous period

of deal making and will acquire …ner information on the distribution of cash

‡ows held by di¤erent types of clients. When imitators enter the market, this

endogenously generated information advantage will make them the “expert”

banker. The expert banker will be able to o¤er better deals to institutions

than the competition and realize a positive pro…t. In short, this paper is a

particular application of Bayesian learning to corporate …nance: investment

banks learn about the uncertainty in the market of corporate underwriting

from past deals, and they are di¤erentiated by the time at which they start

the learning process. Thus, moving …rst puts them ahead in the learning

curve.

In another testimony by a practitioner, we can …nd additional evidence

that bankers learn from the deals made in the early issues of a new …nancial

product: “Financial Innovations such as Credit Derivatives, are not like pro-

ducing a new car, where you just sell it once manufactured. In every deal

7

the Innovation changes: it is perfected to better suited the client’s needs. By

the …fth or sixth deal you are able to sell a much better product,” (Tom No-

bile, Managing Director, Bank of NY).[16] To this date, we know of very few

applications of Bayesian learning in corporate …nance (perhaps most notable

being that one of Diamond [7]). We believe that this paper shows that mod-

eling the dynamics of learning is promising to understand better the nature

and the facts of product innovation in …nance more generally.

In the next section we describe brie‡y some case studies in innovation of

…nancial products with the objective of illustrating better the type of asym-

metry that our model exhibits. Then, we continue by modeling the pro…t

maximizing behavior of investment banks that either create a new …nancial

product or imitate it and their counterparts in the deal. We characterize a

generic contract that can resemble a part of a credit derivative transaction

(e.g. a credit risk swap) or the securitization of an asset (e.g., a mortgage or a

loan) and specify the pro…ts that accrue to each of the parties in the contract.

The third section presents the general set-up in which innovators develop an

information advantage over imitators by moving …rst in the earliest stage of

the game. The learning process is formalized in the general case and then

a simple case is used to solve for the equilibrium in the subsequent section.

8

There we show how it is optimal for an investment bank to innovate in the

…rst stage when it chooses between developing and marketing an innovation

or not. The …nal section summarizes our results.

2 Some Cases of Product Innovation in Fi-

nance

In this paper we argue that the innovator of a …nancial product derives the

advantage that ultimately makes it pro…table to move …rst rather than free-

ride from the fact that he positions ahead of his competitors in a learning

curve. Below we discuss some well document cases in the literature in which

we can see that the innovators had private information about their prod-

ucts and were keen not to disclose more information than they were legally

required. This will …x our ideas for the theory presented afterwards.

2.1 The Securitization of Charge-Card Receivables

The securitization of the American Express charge-card receivables by Lehman

Brothers in 1992 is a case that matches very well the model of innovation

we suggest. By February 1992, the portfolio of outstanding charge-card col-

9

lectibles was not was not traded as a security. Mason et. al. [12] suggest

that “... Lehman saw the American Express charge-card deal as an important

demonstration of its structuring abilities and as a means bywhich it could fur-

ther establish itself as an innovative and leading underwriter of asset-backed

securities”.10 Thus, the possibility of underwriting a large share of charge-

card receivables motivated Lehman Brothers to come up with a new security,

di¤erent to the existing credit-card-backed or …xed-asset-backed securities.

It consisted on issuing debt collateralized by a portfolio of charge-card receiv-

ables. Interest payments to the holders of the security were …nanced by an

additional discount on the purchase of the receivables, which was declared as

the yield and used to provide a liquidity cushion against the risk of default.

Note that asset-backed securities traded before the charge-card-backed prod-

ucts used …nancing charges to pay interest, but charge-cards do not collect

…nance charges.

In the …rst deal, 6’995,152 accounts were selected at random from Amer-

ican Express’s portfolio and bundled in a master trust. These accounts

amounted to $2.4 billion, while the total value of outstanding charge card

receivables was $6.9 billion. Later, the underwriter and the issuer had the

1 0By that time, a large share of Credit-Card receivables had already been securitized byCitibank and First Boston and where publicly traded.

10

faculty to add or remove accounts from the trust. As documented by Ma-

son et. al. [12], the securitization process allowed them to isolate accounts

and have information on the trust performance on a monthly basis. For the

sale prospectus though, it was not required to disclose individual account

information, just aggregate statistics.

2.2 Nikkei 225 Put Warrants

The Nikkei 225 Put Warrant was a complicated transaction by which invest-

ment banks underwrote the issue of a put option on the performance of the

Nikkei 225 index. Issuers were generally sovereign …rms and the security was

traded in the United States (American Stock Exchange). Goldman, Sachs,

Inc. was the …rst investment banker to underwrite such issues. The …rst deal

was completed in January of 1990.

This innovation was attractive to American investors because they were

able to hold a security that would allow them to bet against the Nikkei 225

Index by buying the put option (expectations then were that the Nikkei 225

would soon revert its upward trend, and it did). Sovereign issuers could use

this security as a cheaper source of …nance, given the expectations in the US

market about the Nikkei 225. Since the probability that the holders would

11

exercise their option was high, Goldman, Sachs swapped with the issuers the

risk of conversion and hedged this risk itself in its investment portfolio.

Since then, Goldman pioneered this type of deal in the 1990s and was, for

a decade, the only investment bank to underwrite such a deal for issuers that

were not the bank itself (the investment banking departments of Salomon

Inc., Bankers Trust and Paine Webber underwrote these products but their

own investment divisions were the issuers). In fact, Goldman started engi-

neering put warrants type of deals but using di¤erent indexes, like France’s

CAC-40.

It is also worth noting that Goldman’s hedging positions for each one of

these deals were not disclosed (see Ryan and Granovsky [21])

2.3 Other Cases

Some anecdotal evidence also exhibits similar factures as the ones described

in the cases above. Thackray [23], for example, documents how Drexel,

Brunham, Lambert did not disclose its “junk-bond” prospectuses to Wall

Street insiders because of fears that competitor’s imitations may challenge

their lead in the market for underwriting high-yield debt. J.P. Morgan’s lead

in underwriting asset-backed securities using its so called BISTRO variety

12

of a collateralized loan obligation arguably hinges on the discretion with

which it manages the pool of assets used as collateral (Roper [20]). Salomon

dominated the market of ELKS (equity-linked securities), its own creation,

and also managed the pool of backing assets at its discretion.

3 The Structure of the Model

In the subsections that follow we introduce the information structure which is

general to the class of …nancial innovations discussed throughout the paper.

3.1 Asset Holders and their Types

We de…ne a set of relevant states of the world Z =f1; 2; :::; Zg; which repre-

sents the set of all possible contingencies of the cash ‡ows of the assets that

di¤erent …rms or institutional investors have full claim to. Henceforth, we

shall refer to these agents as issuers. Essentially, as we shall see this cash‡ow

is used to back the issue of a new security, hence the use of that notation.

The true state, Z; will be a random draw from of a prior distribution G(Z)

over the set Z . The knowledge of this distribution is common to all invest-

ment banks. The actual realization of Z is unknown and will not be observed

13

ex-post either.

There is a …nite set of types of issuers, i.e., potential clients of the banks,

F =f1; 2; :::; Fg: For each type there are many identical issuers and the cash

‡ow of any one of type f is itself a random variable whose distribution is

conditional on the state of the world. Let each unit of this cash ‡ow be

denoted by Xf ; and let Hf(xjZ) be its distribution conditional on the state

of the world that is realized. As we will see below, from the knowledge of

this distribution and the observations of X something can be learned about

the true realization of Z.

The notion of a type in this context, can be understood more intuitively

by relating it to the examples mentioned above. When Lehman Brothers up-

dated the selection of accounts in the pool of American Express charge-card

collectibles they used information of the credit pro…les of the holders. Simi-

larly, Salomon Brothers had to form a pool of stocks to back the repayment

of the issue of equity-linked securities dubbed ELKS. The types of stocks

selected would be the types we refer to here, and would be those that are

particularly related to the dividend stream stipulated by the security issued.

In the case of mortgage-backed securities, the types can correspond also to

the risk pro…les of the borrowers, which is e¤ectively approximated by the

14

geographical distribution of the loans.11

3.2 The Contract

Here we model a private contract between a potential issuer with claims to Xf

and a banker. In this contract the issuer agrees to sell the payment stream it

owns to the investment bank in exchange for another cash ‡ow with di¤erent

characteristics. In general, these two cash ‡ows mayhave di¤erent credit risk,

di¤erent types of indexation (currencies, commodity prices, interest rates),

and di¤erent degrees of association with other random variables.

Formally, the type f will sell ®f units of its payment stream, which has a

certain dependence on the realization of the unknown state of the world. In

exchange for each unitXf ; she gets one unit of the payo¤ stream Y; which has

a di¤erent dependence on z:12 For each unit exchanged, the banker charges

a transaction fee, s:13

1 1Coincidentally, Fannie Mae, the largest issuer of mortage-backed securities and col-lateralized mortgage obligations started reporting publicly the disaggregation of the poolof securiticized mortgages in its 2001 Information Statement. The …rst mortgage-backedsecurities were introduced in the early 1980s.

1 2 In general, Y can be made contingent on many observable random variables. Creditderivatives will often provide insurance to …nancial institutions by swaping their uncertaincash ‡ow for one which is tied to a more popular and less volatile index, e.g., tied to LIBOR.Y can also be a payment in cash if the banker is just buying outstanding loans to poolthem.

1 3This fee would be equivalente to the unit underwriting spread.

15

It is important to stress the fact that the market for these private con-

tracts di¤ers from a generic product market in which there are many potential

buyers of a product and where every seller cannot monitor each transaction

made by their competitors. The market for private …nancial contracts de-

scribed here is a market where the bank’s counterparts (the issuers) are

institutional investors or big corporations, so each transaction can be moni-

tored. In e¤ect, however, many details of such contracts are generally kept

private for some time, and the very fact that they can be monitored makes

it easier to detect any infringement of the con…dentiality agreements on the

part of the clients. Thus, the adverse e¤ect on the reputation of the clients

constitutes a strong incentive to honor the agreement.

3.3 The Innovation

Investment banks pool di¤erent types of payment streams and form a port-

folio which is suited to the objectives of the bank. For example, the pool

may be used as collateral for the newly issued security (which is sold to out-

side investors), or it may be used to hedge the current positions that the

bank itself has. In the case of mortgage-banked securities, the pool of out-

standing mortgages was used to back the payment of interest of the di¤erent

16

tranches of securities issued. In the case of the Nikkei 225 Put Warrants,

the bankers insured the issuer of the put on the Nikkei index by swapping

away from them the risk of investors exercising the put option and hedg-

ing the risk themselves in their own investment portfolio. A wide array of

credit derivatives also falls in this category. Some examples are Interest Rate

Swaps, Collateralized Debt Obligations, and other highly structured debt in-

struments in which investment banks swap with the issuers the default risk

of a pool of assets.

The innovation here is essentially the development of the payment func-

tion Y that issuers would trade for their own income stream. However, an

important part of doing deals using this new contract is making them with

the right types of issuers, i.e., getting right the types of cash ‡ows more suit-

able for the pool. More speci…cally, the innovation will be fully determined

by Y and the tuple ® 2 <F of the proportions of each type of investment

cash ‡ows that form the bundle. We will call this vector ® the bundle spec-

i…cation. In other words, the innovation consists of a new way to swap the

cash ‡ow of issuers, and a clever way of bundling them together.

We take as given the fact that the deal is attractive to the issuer because

the new income stream Y is more convenient than their current stream Xf :

17

it may have a lower credit risk or be negatively correlated with some other

income streams they have.

We will assume that in every deal, the component Y is the same regardless

of the issuer’s type that the investment bank deals with. Given this, a generic

contract with a type f institution can be fully characterized by the two

variables (®f ; s): ®f denotes the amount of cash ‡ow owned by institution f

that will be swapped for an equivalent amount of Y and s denotes the per

unit fee charged by the investment bank for this transaction.

We assume that every banker has a bound on the number of units of cash

‡ows it can swap. Without loss of generality we can normalize this upper

bound to one and have:

0 · ®f · 1 8f 2 F ; (1)

X

f2F®f = 1;

that is, ® belongs to the unit simplex in F:

18

3.4 Pro…ts from the Deal

In general, if a banker purchases an amount ®fXf from a type f issuer; it

will give in exchange ®fY . In addition, it will charge a fee ®fs: The revenue

for a type f issuer, net of the underwriting fee would be:

®f (Y ¡ s): (2)

On the other hand, the revenue of the investment bank for that one deal

would be:

®f(Xf + s):

On aggregate, from all the deals signed, an investment bank would make a

net revenue of:

X

f2F(®fXf + ®fs¡ ®fY ) = '(z) + s¡ Y; (3)

where we have introduced the following notation:

'(z) ´X

f2F®fXf(z) 8z 2 Z :

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3.5 Description of the Game

We model …nancial innovation as a three stage game of a …nite number of

investment bankers, indexed by i = 1; 2; :::; I:

Each stage is a time period t = 0; 1 and 2:

At t = 0 one of the banker decides whether or not to invest in the in-

novation, paying an R&D cost C to develop a new type of private

…nancial contract (e.g., a credit derivative or an asset-backed security).

The probability that this innovation is successful, i.e., that it will at-

tract institutions and induce them to sign deals with the banker will be

µ 2 (0; 1). Two bankers developing the same instrument simultaneously

is a zero probability event.

At t = 1 only the banker that paid C moves. We call this investment bank

the innovator. It will sign underwriting contracts with a set of issuers.

At t = 2 the design of the new …nancial product is revealed to the investment

banks that did not innovate (the imitators). They can implement this

new design without paying C and be certain that it was a success.

The business of this innovative deal making becomes competitive: all

investment banks now engage in Bertrand Competition in underwriting

20

Innovator: Choose a, s Observe signal Choose a, sYes

Imitators: No move Observe Y Choose a, s

No Game Over

Innovator: Pay C?

t = 0 t = 1 t = 2

Figure 1: An illustration of the timing of the game. There are three periods,and only the banker that pays the R&D cost in period 0 moves in period 1.In period 2, the innovator and its imitators compete for market share. Theinnovator has had one previous period of making deals, that allowed him toextract a private signal.

fees.

See Figure 1 for an illustration of the timing described above.

3.6 Interpretation of the Game

At the start, an investment bank has to decide whether to develop or not a

…nancial product. This product has a development cost C; and it is designed

to attract issuers that hold claims to certain types of random cash ‡ows.

Once developed, the innovator makes the …rst underwriting deals, being the

only underwriter of the issues using such a contract. Immediately after the

…rst contracts are signed, some information about them always …lters out

21

to other investment banks that become able to imitate the product.14 The

market for this type of underwriting becomes competitive then. By the time

imitation comes in, though, the innovator has already concluded some deals

and has been able to gain some expertise. This will allow him to perfect the

deal and, in particular, to improve the underlying money making scheme.

This idea is summarized by the following testimony: “In Credit Derivatives,

imitators can fully understand our new product but they don’t know how to

make money with it,” (Andrei Paracivescu, Credit Derivatives Trader, J.P.

Morgan.)[17]

The result of learning-by-doing is an information advantage of the devel-

oper over the imitators. In our framework, the innovator will have learned to

match more appropriately the di¤erent types of institutions’ payment streams

creating a better portfolio of deals, i.e., enhancing his money-making scheme.

Since the innovator’s benchmark contract or terms-sheet is revealed (in this

model what is revealed is Y; or what to swap X for), the imitators can make

their own deals, o¤ering the same contract but they will not have the same

skill and expertise as innovators in creating the portfolio of deals. Again, as

1 4Although these kinds of private contracts are strictly con…dential, information is leakedin various ways: the client may go to other investment banks to seek a better fee, or peoplethat develop these products may be hired away to competing banks.

22

a Wall Street practitioner puts it, “everybody can see the laid-out contract

but what I am careful not to disclose are the positions in my book. With this

information you could track down the logic and see where I make money,”

(Andrei Paracivescu, Credit Derivatives Trader, J.P. Morgan.)[17]

4 The Innovator’s Learning Process

In this section we explain the mechanism through which this learning-by-

doing occurs, and illustrate what is the private signal that allows the innova-

tor to have asymmetric information which is advantageous over its imitators.

4.1 The General Set-up

To …x ideas, let F = Z so that there are as many types of issuers as states

of the world. Issuers of any type can have either a high cash ‡ow, H; or a

low one, L: “Good” states for di¤erent types will be those states where the

probability of having a high cash ‡ow is greater than having a low one; “bad”

states will be those in which the latter is not true. To simplify, we assume

that for each type there is only one good state. Further, we will assume that

this state is only good for that type of …rm. Without loss of generality, let

23

the good state for any arbitrary type f 2 F be such that z = f . Thus, we

can summarize Hf (xjz) by:

Pr(Xf = Hjz = f) = 1¡ "; (4)

Pr(Xf = Hjz 6= f) = °;8f 2 F ; z 2 Z ;

where " and ° are small enough (all we need is for them to be smaller than

12 ). Figure 2 illustrates these conditional distributions, for the case of Type

1 issuers.

Consider the case of an investment bank that has no information about

the true state of the world. The bank knows the prior probability distribution

G(Z) over the states that, to keep things simple, we assume to be the uniform.

An innovator gets a signal in the …rst stage. This signal, ex; gives him a more

accurate knowledge of the realized state of the world. It is an F -dimensional

vector of the cash ‡ows of each institution from each type realized in the …rst

stage, formally, ex 2 fH;LgF : Conditional on this signal, and the distributions

given by (4), the innovator updates his prior beliefs on the actual realization

of the state of the world. Notice that the signal can be mapped in two

subsets of types: one containing those types that had high cash ‡ows (the

24

z = { 1 , 2 , … , Z }1 - e H

1

e L

1 / Z? H

21 / Z

1 - ? L

z ...

1 / Z

? H

z

1 - ? L

Figure 2: Conditional probability distribution function of the cash ‡ow thatan issuer of Type 1 has claims to. z is the underlying random variable thatintroduces uncertainty in the cash ‡ow, and there are Z possible states ofnature, one being the “good state” for each type. Note that H > L:

25

“high types”) and the other containing those that did not (the “low types”).

4.2 Bayesian Updating

For a uniform prior we have that 8z;Pr(Z = z) = 1Z : The generic signal will

be a sequence of H and L. Now, we can de…ne the sets

H = ff 2 FjXf = Hg and L = ff 2 FjXf = Lg;

and let #(H) = h and #(L) = l, so that h+ l = Z:

Then for any state j 2 H , the posterior probability that this was the

realized state would be given by:

Pr(z = j jex) =

=(1¡ ")°h¡1 (1¡ °)l

hh(1¡ ")°h¡1 (1¡ °)l

i+ l

h" (1¡ °)l¡1 °h

i

=1

h+ lh"

1¡²°

1¡°

i =¸

Z + h [¸ ¡ 1];

26

where ¸ ´h1¡"²

1¡°°

i> 1 for " and ° small enough: For states k 2 L,

Pr(z = kjex) =

=" (1 ¡ °)l¡1 °h

hh(1¡ ") °h¡1 (1¡ °)l

i+ l

h" (1¡ °)l¡1 °h

i =

=1

hh1¡"²

1¡°°

i+ l

=1

Z + h [¸ ¡ 1]:

Then, for most signals, i.e., for h = 1; 2; :::;Z¡ 1; there will be updating, i.e.:

Pr(z = j jex) > 1Z> Pr(z = kjex):

Notice that the di¤erence between the probabilities above is ¸¡1Z+h[¸¡1] ; which

is decreasing in the observed number h of high types. Intuitively, the set of

states of the world is partitioned in one with those more likely states and

another with the less likely. The smaller h; the smaller the set of more likely

states and the larger its complement. Thus, each state within the smaller set

has more probability of being the realized one.

Note that the signals (H;H; :::; H) and (L;L; :::; L) don’t allow any up-

dating of the prior distribution G(Z): The probability that the innovator

gets a signal which allows updating, and in consequence, the probability of

27

having superior information for the next issues of the new instrument is:

» = 1 ¡ (1¡ ")°Z¡1 ¡ "(1¡ °)Z¡1: (5)

4.3 Portfolio Choice for Innovators at t = 2

In this model investment banks choose a contract (®; s) to maximize the net

revenues given by (3) and taking as given the maximizing behavior of the

issuers that they deal with. Since the fee s does not a¤ect the value of the

bankers portfolio, '(z); we can break down the optimization problem in two

parts. First, banks solve the following problem:

choose ® = (®1; ®2; :::; ®F ) to maximize E [' (z)] (P1)

subject to ® 2 ¢F ;

and V ar[' (z)] · V:

Investment banks are maximizing the expected value of their portfolio

subject to the constraint that they cannot a¤ord a limited volatility of returns

in their portfolio.15 We assume that V is small enough so that the constraint

1 5This volatitlity restrictions are common practice in portfolio management. Besides,this constraint also allows to solve the indeterminacy on the weights ® of all the H types

28

is binding. This will imply that the problem has an interior solution: ®¤ 2

(0; 1)F : Moreover,

Lemma 1 The Lagrangian for (P1), ¤; is symmetric with respect all ®f such

that f 2 H and all ®g such that g 2 L:

¤(:::; ®i; :::; ®j; :::) = ¤(:::; ®j; :::; ®i; :::) 8i; j 2 H;

¤(:::; ®g; :::; ®h; :::) = ¤(:::; ®g ; :::; ®h; :::) 8g; h 2 L:

Proof. See appendix.

This will imply that the solution arising from the …rst-order condition is

also symmetric:

®i = ®H 8i 2 H, (6)

®i = ®L 8i 2 L.

With updated beliefs on the states of the world, an informed banker will

now form bundles that put more weight on the high types. That is, ®H > ®L:

and all the L types. Alternatively, a problem in which bankers have mean-variance utilitywould produce the same result.

29

4.4 Portfolio Choice of Uninformed Bankers

Imitators, or innovators at t = 1; know only a prior distribution of the true

state of the world. That is, they have not had the chance to observe the signal

ex and update their beliefs. Given this information, and given the symmetry

of (P1), an uninformed banker can only form bundles with all the types of

…rms weighted symmetrically. That is, ®f = 1F 8f:

The con…dentiality agreements guarantee that imitating banks are pre-

vented from gathering crucial information, such as the bundle speci…cation,

from the innovator’s clients. In reality, it is observed that bankers make

sure that their bundle speci…cation is not disclosed early enough. For ex-

ample, in the American Express Charge-Card securitization case, only the

aggregate value of the accounts pooled was publicly reported, and not the ac-

tive management of the portfolio. Similarly, as we mentioned before, Drexel,

Brunham, Lambert were careful to keep private the order-‡ow of their “junk-

bond” deals. In more recent cases, it has been well documented that due to

discretionary management of the pools backing collateralized loan obligations

it is impossible to observe the positions and to be rated by Standard & Poor

(See Roper [20]).

Perhaps this fact is best summarized by a recent statement in the Recom-

30

mendations for Disclosure of Trading and Derivatives Activities of Banks and

Securities Firms, by the Basle Committee on Banking Supervision, on Febru-

ary 1999: “institutions should disclose information produced by their internal

risk measurement and management systems on their risk exposures and their

actual performance in managing these exposures. Linking public disclosure

to internal risk management processes helps ensure that disclosure keeps pace

with innovations in risk measurement and management techniques.”[2].

4.5 A Simple Case of Learning: Two types, Two states

The discussion above argues that …rst-movers are able to assign higher prob-

ability of occurrence to those states that are good for the institutions that

had high cash ‡ows at the …rst stage of the game (and lower probability to

the other states). Next, we develop the model for a simpler case where …rms

can be of one of two types only.

In the …rst stage, the …rst-mover develops the bundle with equal weights

for each type, i.e., ®1 = ®2 = 12: Imitators in the second stage have the same

information as innovators had in the previous period. Thus, they can only

form the (12;12) bundle.

Signals are drawn out of the set f(H;H); (H;L); (L;H); (L;L)g condi-

31

tional on the realized state of the world. Notice that, in this symmetric

case, the signals (H;H); (L;L) do not allow any updating. From (5), this

probability equals " + ° ¡ 2"°:

If the …rst mover observes any of the two signals that allow him to update

his prior beliefs G(Z) then he will form a bundle in the second stage with

larger weight on high types. Let this weight be ®H. Then, it is clear that

®H > 12 > ®

L = 1¡ ®H :

An event in this world is characterized by the triple (Z;X1; X2): Four of

the eight possible events involve non-informative signals and in two of them

the realized state is not the most likely one, given the signal. In the latter

cases, the future cash ‡ows of the …rm with more weight in the bundle would

be low with a large probability.

Based on this information structure we compute the expected payo¤s of

imitators’ and innovators’ portfolios using the Lemma below.

Lemma 2 In the case where Innovators can update their beliefs on the re-

alization of the state of the world, i.e., when the signal is informative, we

32

have:

E('In) = f®H (1¡ °)(1¡ ")(1¡ °)(1 ¡ ") + °" +®

L °"(1 ¡ °)(1¡ ") + °"g[(1¡ ")H + "L] +

f®H °"(1¡ °)(1 ¡ ") + °" +®

L (1¡ °)(1 ¡ ")(1 ¡ °)(1¡ ") + °"g[°H + (1 ¡ °)L];(7)

E('Im) =12[(1¡ ")H + "L] +

12[°H + (1 ¡ °)L]: (8)

Proof. See appendix.

Lemma 3 In the case where Innovators receive uninformative signals, the

portfolio of innovators is equal to the imitators’ and so are their corresponding

expected returns, which equal:

E('In) = E('Im) =12[(1¡ ")H + "L] +

12[°H + (1¡ °)L]: (9)

Proof. See appendix.

Our goal now is to show that, when learning occurs, the innovator will

have a better portfolio of deals than the imitator. The reason for this is

straight forward: the innovator’s bundle has more units of cash ‡ows of

institutions of the high types and these are ex-ante more likely to have high

33

returns in t = 2:

Proposition 4 Whenever Innovators get an informative signal, E('In) >

E('Im):

Proof. See appendix.

Note that even though in some nodes of the last stage innovators will be

no di¤erent than imitators, the probability of reaching these nodes is small.

The event that there is no learning from the innovator becomes less likely

as the number of types increases: the number of uninformative signals is

always only two, while the total number of possible signals is 2F : This is

seen formally in equation (5), as @»@F> 0: This is intuitive: the more deals

across di¤erent types an innovator makes, the more likely it is he will learn

to improve his portfolio and the higher the pro…t margin he will have with

respect to imitators, as we will see below.

4.6 Issuers’s Choice

All issuers that sign this underwriting contract are willing to swap all their

units of X for the new payment stream Y: Since all investment bankers

o¤er the same per unit cash ‡ow Y; the institutions will be attracted to

34

the banker that charges the lowest underwriting fee, s: That is, they choose

i 2 f1; 2; :::; Ig to maximize Y ¡ si:

5 The Equilibrium

5.1 Bertrand Competition

We assume that investment banks will compete à la Bertrand in fees by

undercutting each other. The undercutting process will reach a halt when

imitators make zero pro…ts. As a result, the equilibrium fee will be given by

the imitators’ zero pro…t condition:

s¤ = Y ¡ E('Im): (10)

This will be the equilibrium underwriting fee charged to issuers. Indeed, for

that fee, the innovator makes the pro…t :

E('In) ¡ Y + s¤ = E('In) ¡ E('Im): (11)

If the pro…ts in (11) are positive, the pioneer will be able to marginally lower

his fee further to attract more institutions, as we will show later.

35

Proposition 5 At t = 2; imitators make zero pro…t in equilibrium and the

innovator makes pro…t E('In)¡ E('Im):

Note that the higher the wedge between the expected returns of the port-

folio of innovator over the imitators’, the larger the developer’s pro…ts. The

innovator’s pro…ts are determined by the extent of the learning-by-doing in

the …rst stage, that is, by how much he learnt how to improve the money-

making scheme in the second round of underwriting with respect to the …rst.

Of course, in the unlikely event that there is no learning (no improving of

the portfolio of deals), competition by imitators will drive innovator’s second

stage pro…ts to zero.

5.2 Market Shares

If there is learning the developer’s pro…t will be positive and it will allow

him to undercut the fee s¤ further by, say, an epsilon, and swap as many

units of Y for X until his capacity constraint is reached. This will leave

imitators to share the rest of the underwriting market. If we assume that

issuers represent the short side of this market, the underwriting contracts

will be rationed across imitators. Even though all investment banks have the

same capacity, the equilibrium market shares of innovator and imitators are

36

not the same. Since the innovator has the information advantage, he chooses

a lower fee that allows him to underwrite deals at full capacity.

As in standard Bertrand competition, in this model each imitator’s share

of the new product’s market is really undetermined because they make zero

pro…ts. Since the imitators are identical we can assume that the contracts

that remain to be underwritten after the innovator has taken his share are

equally rationed among them, following the general convention for Bertrand

allocations. This will leave the innovator being the market leader, i.e., having

the biggest market share.

Notice that it is not important that the innovator has a larger market

share. Just because he is better informed about the state of the world, he

is the only bank that can work at full capacity for any size of the market of

potential issuers, and he is the only banker making pro…ts with free-entry.

Here we illustrate that this model can have as a prediction the market-shares

leadership fact by assuming that imitators ration the proportion not under-

written by the innovator.

37

5.3 Optimality of Innovating

The …nal step is to …nd the optimal choice of the potential innovator and

the equilibrium allocations resulting from this choice. At t = 0 this bank

must decide whether or not to pay the development cost C. The potential

developer will have to take into account that the innovation is risky: if he

develops and pays C, there is a probability µ that the new product attracts

institutions, but with probability 1¡µ the innovation will not be marketable,

and the developer will make a loss.

If the innovative product proves to be successful, the developer will have

to face competition from imitators. Imitators will enter the market after they

see the …rst innovative deals. The developer’s pro…ts from these …rst deals,

i.e., in the learning stage, are zero. This is because in this stage the newly

established innovator has the same information and expertise as an imitator

in the next stage. So, since the time lapse between the introduction of a new

…nancial product and the appearance of imitations is typically very short, an

innovator in the …rst stage e¤ectively competes in fees with the imitators.

With no time discounting, if an innovator charges a higher underwriting

fee institutions will prefer to wait for the next period and make a more

38

convenient deal with an imitator.16 As a consequence, for the investment in

the development of a new product to be worthwhile, the developer will have

to make positive pro…ts in the last stage, when competition from imitators

drives pro…t margins down.17 The developer will have on his side additional

expertise and information over is competitors. In our model, this will happen

if and only if some learning occurs in the …rst stage, that is, with probability

»: With probability 1¡ »; the innovator will have no comparative advantage

with respect to his imitators and will make zero pro…t.

To summarize, at t = 0; the expected pro…ts for a bank that decides to

invest to develop the innovation are:

µ[»(E('In) ¡ E('Im)) + (1 ¡ »)(0)] + (1¡ µ)(0)¡ C:

That is, at the start of the game, a potential developer will pay the develop-

1 6 Indeed, when o¤ered an innovative deal by its developer at a given price, institutionsoften search around to see if other bankers can o¤er them a cheaper deal. As we men-tioned, this is one channel through which some strictly con…dential information about theinnovation is transmited to potential imitators. In reality, as we mentioned, what is ratherdisclosed is the new swap technology, Y:

1 7This result is consistent with the evidence that Tufano [26] found: when they arethe sole underwriters, innovators do nto charge fees larger than when they compete withimitators.

39

ment cost C if and only if:

µ»[E('In)¡ E('Im)] ¸ C: (12)

Note that » increases in F: That is, the more deals a pioneer is able to make

prior to imitation, the higher the likelihood that he will gain expertise over

his competitors from his …rst issues and that he will perfect the way to make

money using this new way …nancial product. This constitutes his …rst-mover

advantage.

Despite the absence of patents and the possibility of cost-less and early

imitation, investment in R&D is still pro…table for the investment banks.

The monopolistic advantage derived from the …rst stage learning guaran-

tees positive pro…ts for innovators in the second period. Imitation may look

attractive because it is cost-less but, for this same reason, has the disadvan-

tage of being undertaken by almost all other banks: competition is …erce and

generates low (zero in our model) pro…ts.

40

6 Summary

Using a simpli…ed 2-by-2 version of our model we have concluded that in-

vestment banks have the incentive to pursue in the discovery and marketing

of a new …nancial product even in the absence of a patent that guaran-

tees a pro…table period of monopoly for the issuer. Innovation takes place

through an investment bank’s underwriting business: it makes an innovative

exchange of outstanding payment streams owned by …nancial institutions for

newly designed payment schedule. The incentive to innovate despite cost-

less imitation is given by the supra-normal pro…ts earned when exploiting

the information asymmetry generated by the learning from the …rst private

deals.

Our …nancial product is an innovation in the sense that the developer has

to pay a development cost to try to discover a new payo¤ function which will

attract institutions by providing improved hedging to their own cash ‡ows.

Like many other innovations, once one agent pays this development cost and

the innovation proves successful, there is no need for competitors to pay it

in order to market the imitation.

As innovators update their beliefs on the likelihood of di¤erent types hav-

ing higher earning streams they can pick the right institutions to sign the

41

deals with in order to match them more e¤ectively in a portfolio. It is impor-

tant to stress that what makes innovation pro…table in this model is that the

innovator exploits an information advantage in the competitive stage. Also,

it is worth pointing out that the short lead time of the innovator merely

provides him an informational advantage and not a temporary monopoly

pro…t that could justify on its own the development stage expenditures. The

supra-normal pro…ts here are realized only during the imitation stage.

In this paper we have also explained why an innovator might end up

having the largest market share of the market for underwriting.

42

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46

Appendix

Proof to Lemma 1. We ommit a proof, since we believe it is veri…ed

only by inspection.

Proof to Lemmas 2 & 3. In any state, one of the two …rms in the

bundle will have high cash ‡ows with a probability 1¡ " and the other with

probability °:When innovators receive an informative signal and form up the

bundle with larger weight for the good type, the true state could be indeed

the one suggested by the high signal, in which case the expected payo¤s of

the bundle would be

®H [(1 ¡ ")H + "L] + ®L[°H + (1¡ °)L]: (13)

In case the true state is not the most likely one, given the signal, the expected

payo¤ of the same bundle would be

®L[(1¡ ")H + "L] +®H [°H + (1¡ °)L]: (14)

Now then, the probability of receiving a “correct ” informative signal, i.e.,

the one where the good type has a payo¤ of H, is (1¡")(1¡°)(1¡")(1¡°)+"° while the

47

probability of getting incorrect signals is "°(1¡")(1¡°)+"° :

The expected payo¤ to the innovators’ bundle at any node of the game

where the signal was informative is then nothing but the weighted average

of equations (13) and (14):

E('In) =(1¡ ")(1¡ °)

(1 ¡ ")(1¡ °) + "°f®H [(1¡ ")H + "L] + ®L[°H + (1 ¡ °)L] +

"°(1 ¡ ")(1¡ °) + "°f®

L[(1¡ ")H + "L] + ®H[°H + (1 ¡ °)L]g

= f®H (1¡ ")(1¡ °)(1¡ ")(1¡ °) + "° +®L

"°(1 ¡ ")(1¡ °) + "° g[(1¡ ")H + "L] +

f®L (1 ¡ ")(1¡ °)(1¡ ")(1 ¡ °) + "° + ®H

"°(1 ¡ ")(1¡ °) + "° g[°H + (1 ¡ °)L]:

For any uninformative signal, innovators choose equal weights for each

type of institution. Thus, in any event the expected payo¤ of the portfolio

is:

E('In) =12[(1¡ ")H + "L] +

12[°H + (1¡ °)L]: (15)

Imitators behave just like innovators who have received signals that allow

no updating. They assign equal weights to each type in the bundle, thus the

48

expected payo¤ of their portfolio is given by:

E£'Im

¤= E ['jz = 1]Pr [z = 1] + E ['jz = 2]Pr [z = 2] (16)

E ['jz = 1] = E ['jz = 2] =12[(1 ¡ ")H + "L] +

12[°H + (1¡ °)L];

which yields:

E£'Im

¤= E ['jz = 1] (Pr [z = 1] + Pr [z = 2]) =

=12[(1¡ ")H + "L] +

12[°H + (1 ¡ °)L]:

It is important to notice that this last result does not depend on the prob-

ability distribution. Imitators believe that Pr[z = 1] =Pr[z = 2] = 12; the

common prior. Once Innovators have updated their beliefs they will in gen-

eral …nd new di¤erent values for this probabilities. Therefore, it could be

argued that imitators are “wrong”, i.e., less accurate than the one made by

innovators that have learned more about the state of the world. However,

given the symmetry of this setup this is not an issue here: E£'Im

¤does

not depend on the probability distribution. Probabilities add up to one and

cancel out, since they multiply a common symmetric factor.

49

By assumption, H > L, 0 < "; ° < 12 and ®H > 1

2: Now,

E('In ¡ 'Im) = f®H (1¡ ")(1 ¡ °)(1¡ ")(1¡ °) + "° +®L

"°(1 ¡ ")(1¡ °) + "° ¡ 1

2g[(1 ¡ ")H + "L] +

f®L "°(1 ¡ ")(1 ¡ °) + "° + ®H

(1¡ ")(1¡ °)(1 ¡ ")(1¡ °) + "° ¡ 1

2g[°H + (1¡ °)L]:

Substituting for ®L = 1 ¡ ®H;

E('In ¡ 'Im) = (®H ¡ 12)[(1 ¡ ")H + "L] ¡

(®H ¡ 12)[°H + (1¡ °)L]

= (®H ¡ 12)(1¡ ° ¡ ")(H ¡ L);

which is clearly positive by the assumptions above.

50